Name: Shimano Bb-un300 Square Taper Bottom Bracket
Brand: Shimano
SKU: 4550170619282
Price: 33.0 AUD
Availability: InStock

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:73mm Lgth:113mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:73mm Lgth:118mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:113mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:110mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:115mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:73mm Lgth:122mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:117mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:118mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:123mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:122mm]

Shimano Bb-un300 Square Taper Bottom Bracket [wdth:68mm Lgth:127mm]

Shimano Bb-un300 Square Taper Bottom Bracket [width:68mm Length:107mm]

$33.00

Shipping calculated at checkout.

Low stock - 1 item left
Backordered, shipping soon

The Shimano BB-UN300 is a square taper bottom bracket designed for smooth pedalling performance and long-lasting reliability. With sealed cartridge bearings to keep out dirt and moisture, it’s an excellent upgrade or replacement for bikes using a traditional square taper crankset.

Why Choose the Shimano BB-UN300?

Sealed cartridge design provides low-maintenance durability.
Compatible with square taper (JIS) cranksets.
Available in multiple shell widths and spindle lengths to suit a wide range of bikes.
A dependable option for MTB, trekking, hybrid, and city bikes.

Component	Specification
Model	Shimano BB-UN300
Type	Square taper (JIS) bottom bracket
Shell Widths	68 mm, 73 mm
Spindle Lengths	107 mm, 110 mm, 113 mm, 117.5 mm, 122.5 mm, 127.5 mm
Axle Type	Square taper (JIS)
Bearings	Sealed cartridge unit
Application	MTB, trekking, hybrid, city bikes

Specifications subject to change without notice

All Bikes Are Only Avaliable Through Local Pickup

Please select local pickup at checkout

Australia Post delivery estimates

Parcel Post: 2–4 business days within South Australia; 3–6 business days interstate.
Express Post: 1–2+ business days within South Australia; 1–3+ business days interstate.

Estimates start from the business day after posting and exclude order processing time. Regional and remote deliveries may take longer, especially during busy periods. Express Post does not guarantee next-day delivery to every address.

Christmas 2026 — recommended last lodgement dates

Australia Post recommends lodgement by these dates for the best chance of arrival by Christmas Day:

Parcel Post: Monday 21 December 2026 for most states; Monday 14 December 2026 for parcels sent to or from Western Australia, Tasmania and the Northern Territory.
Express Post: Wednesday 23 December 2026 for most states; Tuesday 22 December 2026 for parcels sent to or from Western Australia and the Northern Territory.

These are Australia Post’s recommended business lodgement dates, not our order cut-off dates or a delivery guarantee. Please order well before these dates to allow time for processing and dispatch from Victor Harbor. Allow extra time for regional and remote locations. Contact us before ordering if you need an item for Christmas.

Australia Post delivery estimates · Latest Christmas sending information

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Shimano Bb-un300 Square Taper Bottom Bracket

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